Functional extension is currently under discussion in the 3rd Generation Partnership Project (3GPP) (for example, refer to NPL 1) that formulates technical specifications for public wireless communication networks.
A method with flexibly using information indicating availability of a service is possible with the functional extension (called Machine-to-Machine equipment). The information indicating the availability of the service is contract authentication information (for example, a revisable connection right). For example, the contract authentication information can be downloaded, the downloading can be temporarily stopped, or the downloading can be resumed, over a network.
Furthermore, currently, the contract authentication information needs to be retained in a physical device called a Subscriber Identity Module (SIM) card. However, a retention method is also made flexible by dealing with the contract authentication information in software.